Heretofore, paperboard, tar paper and other similar sheet material have been secured to generally flat surfaces, such as house roofs and walls, interior walls of railway freight cars and both interiors and exteriors of wooden crates, by nails or tacks having large heads or plates of enlarged size confined hereon and/or secured thereto. Also, it is customary to use this type of fastener for hanging and/or otherwise fastening decorative fabric, crepe paper and ribbons to wooden supports. One of the fasteners in present use is of two piece construction and is composed of a square plate having a small center opening for receiving a small headed nail, of 3/4 of an inch to 11/4 inches in length, which has an upset portion adjacent its head for confining the plate therebetween. After the nail and plate are formed separately, said nail must be inserted through the center opening of the plate and bradded thereto by upsetting or otherwise. The single nail or prong of such fastener must be of appreciable length so as to resist dislodgment thereof. Since the manufacture of this type of fastener involves at least three steps, it is believed to be readily apparent that it would be more economical to eliminate the necessity for one or two of the steps.
Accordingly, the objects of this invention include the provision of a one piece fastener having a quadrilateral, preferably generally square, head and a pair of integral prongs projecting generally perpendicularly and struck from the head in spaced relationship at the medial portion of said head whereby the fastener may be formed from a narrow strip of sheet metal in a one-step relatively simple punching operation that is adapted to be repeated intermittently so as to continually form additional fasteners; whereby the costs of the metal, forming machinery and manufacture of the fastener are minimal due to its one piece construction and the narrowness of the strip sheet metal; whereby all of the metal is utilized without waste in forming the fastener; whereby the pair of prongs may be of less length than the single nail of the more or less conventional single prong fastener due to the greater surficial area of said pair of prongs; whereby the connection provided by the pair of prongs is more positive due to the freedom thereof to converge or diverge; whereby a three-point support for the fastener may be provided by the coaction of the spaced pair of prongs with either one of a pair of diagonally opposed corners of the head; whereby the head may be of different configurations including parallelogrammatic, rectangular, rhomboidal or have one side different from its other sides.